reworking metrics query

backend/services/mgmt/v1alpha1/metrics-service/metrics.go

@@ -98,7 +98,7 @@
 		if !ok {
 			return nil, fmt.Errorf("unable to convert query response to model.Matrix, received type: %T", queryResponse)
 		}
-		usage, err := getDailyUsageFromMatrix(matrix)
+		usage, err := getDailyUsageFromMatrix2(matrix)
 		if err != nil {
 			return nil, err
 		}
@@ -250,7 +250,71 @@
 	}
 }
 
+func getDailyUsageFromMatrix2(matrix model.Matrix) ([]*mgmtv1alpha1.DayResult, error) {
+	dailyTotals := map[string]float64{}
+
+	for _, stream := range matrix {
+		values := stream.Values
+		if len(values) == 1 {
+			ts := values[0].Timestamp.Time()
+			day := ts.Format("2006-01-02")
+			dailyTotals[day] += float64(values[0].Value)
+		} else {
+			prevValue := float64(values[0].Value)
+			prevTs := values[0].Timestamp.Time()
+			prevDay := prevTs.Format("2006-01-02")
+
+			for i := 1; i < len(values); i++ {
+				currentValue := float64(values[i].Value)
+				currentTs := values[i].Timestamp.Time()
+				currentDay := currentTs.Format("2006-01-02")
+
+				if currentDay == prevDay {
+					dailyTotals[currentDay] += currentValue - prevValue
+				} else {
+					dailyTotals[currentDay] += currentValue
+				}
+				prevValue = currentValue
+				prevDay = currentDay
+			}
+		}
+	}
+
+	var dates []string
+	for day := range dailyTotals {
+		dates = append(dates, day)
+	}
+	sort.Strings(dates)
+
+	output := []*mgmtv1alpha1.DayResult{}
+	for _, day := range dates {
+		date, err := parseDateString(day)
+		if err != nil {
+			return nil, err
+		}
+		output = append(output, &mgmtv1alpha1.DayResult{
+			Date:  date,
+			Count: uint64(dailyTotals[day]),
+		})
+	}
+	return output, nil
+}
+
+func parseDateString(dateStr string) (*mgmtv1alpha1.Date, error) {
+	const layout = "2006-01-02"
+	t, err := time.Parse(layout, dateStr)
+	if err != nil {
+		return nil, err
+	}
+
+	return &mgmtv1alpha1.Date{
+		Year:  uint32(t.Year()),
+		Month: uint32(t.Month()),
+		Day:   uint32(t.Day()),
+	}, nil
+}
+
 func getDailyUsageFromMatrix(matrix model.Matrix) ([]*mgmtv1alpha1.DayResult, error) {
 	output := []*mgmtv1alpha1.DayResult{}
 	for _, stream := range matrix {
 		var latest int64
@@ -292,7 +356,7 @@
 }
 
 // combines counts where date is the day and returns a squished list with the original order retained
 func squishDayResults(input []*mgmtv1alpha1.DayResult) []*mgmtv1alpha1.DayResult {
 	dayMap := map[string]uint64{}
 	for _, result := range input {
 		dayMap[toDateKey(result.GetDate())] += result.GetCount()
@@ -308,11 +372,11 @@
 	return output
 }
 
 func ptr[T any](val T) *T {
 	return &val
 }
 
 func timeToDate(t time.Time) mgmtv1alpha1.Date {
 	return mgmtv1alpha1.Date{
 		Year:  uint32(t.Year()),
 		Month: uint32(t.Month()),
@@ -320,7 +384,7 @@
 	}
 }
 
 func toDateKey(day *mgmtv1alpha1.Date) string {
 	return fmt.Sprintf("%d_%d_%d", day.Day, day.Month, day.Year)
 }